Mold cone angle is an important parameter. The simulation of the main molding stage of hydraulic briquetting machine was carried out with the finite element software ANSYS, in which the special ANSYS parametric design language was used to optimize analysis the mold cone angle of hydraulic briquetting press. The relationship between mold cone angle and equivalent stress was studied, along with the relationship between the friction stress and displacement in different mold cone angle values. The result indicated the best range of mold cone angle of 5.5°～6.0° is obtained, in which, the simulation results are approximately in accordance with the measured values. Furthermore, the briquette block has a good density, and quality, and is suitable for storage and transportation.